Electric heater.



PATENTED 00129, 1907.

'G. E. STEVENS. ELECTRIC HEATER. APPLICATION rmm my 23, 1904.

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,MQJWL PATENT-ED 00129 G. E. STEVENS.

ELECTRIC HEATER.

APPLIOATION FILED my 22, 1904.

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GEOJGE STEVENS, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORA'lION OF NEW YORK.

ELE GTRIC HEATER.

Specification of Letters Patent.

Patented Oct. 29, 1907'.

Application filed May 23, 1904. Serial No iZO9tl58.

To all whom it may concern:

Be it known that 1 GEORGE E. S'rEvENs, a citizen of the United States, residing at Lynn, in the county of x and State ot Massachusetts, have invented (cf- 'n new and useful lmpnrvenients in Electric Heaters,

hich the following is a specification My invention relates to electric heaters for water or oth finidl r d has particular reference to that type in which an elec c resistance conductor is employed as the source of heat in ct'intradistinction to the electrolytic type in which the fluid is heated by passing the current through it. I

The principal object of the invention is to provide a heater which will be efficient in operation, compact in structure, and cheap to manufacture.

in carrying out my invention 1 employ a novel organization in which the heating unit is provided with a entral open space and preferably composed of a spiral y-arranged resistance conductor having its convolu- "Lions in close mechanical relation and insulated troni each other and in which the fluid passages are arranged so as to bring the fluid into convective or heat conductive relation with both the interior and exterior oi the trails ot the unit. The heater also u'el'erably degnml for direct connection to a tiuid supply pipe and so proportioned that the fluid will be heated while it pisses through the heater in an uninterrupted stream. This heater may also be constructed as an attachment to he applied directly to a faucet and when so used I empl y a controlling switch which is arranged so as to close the circuit; through the heater when the faucet is turned on, and to break the circuit when the faucet is turned ol l The specific character of the invention will be best understood upon l'clcltuice to the tollowing detailed de- )ilUH taken in connection with the accompanyingdrawing in which i have illustrated the invention in three diihzrent forms.

In said drawings, Figure l is a sectional view of the simplest form ot the invention shown directly connectedto a lnucet: Fig, a plan view of the switch control i the heater circuit; Figs. 3 and 4 illustrate vertical and lit i ontal sections. respectively, of a modiprovided with a plurality of central conit; tubes. the planes of section being indicated by lllll' Ii .E in Fig. -i and 4 4 in Fig. 3, i .spcctivcly; 4. is a vertical se tion of the third form of heater; g, 8 is a :ihatailed view of a portion oi the connecting ring e located at the lower ends of the lulu-s or" this a den \i -w ot the lower cap: and Fig. -ntal section ot the upper cap, the plane of .liltui by the line in Fig. 5.

r to iikej j sistance unit l a switch is employed.

.is' located directly upon the faucet l4 niul' coinprises esllelerring in detail to that form oi the invention illus- 55 trated in Fig. 1. l0 designates a central tube or pipe which opens at its upper end into a chamber formed between the head ll and the cap '12, and communicates at its lower (-nd through any suitable connection, as the tube 15, with the faucet 14 l'rom which water or other fluid supplyis obtained, the connection between the tube 13 and the faucet being in the present instance union couplingl Locatedjust exteriorlyot'thctube l0 is the heating unit 15. This unit preferably consis": of a spirallyhrrangwl re tance conductor composed of 65 a thin strip ot ribbon of iron, steel or other suitable resistance material wound on edge into spiralm'ith its convolutions in ch mechanical relation out separated and protected by e thin lihn of insulation 17. This insulation may be oi any desired hind butpreterribly I 7C employ a l't ietory ins ting compound compo. d ,olkaolin and ieate ot soda. This unit 15 need not be more fully escribed in the present (11:30 since it constitutes no part of the present invention except in so in direct connnu nit ation with the pa go at the upper end of thrtube 19 formed between the parts l! and l2 is a flattened spiral tube 20 which passes around the enterior oi the unit 15 in elo L: pn inity thereto and terminates at the lower end of the tube in an outlet spout 2].

For the purpose of cuttingin and out ot' circuit the relhis switch sentially two tilted terminal clips 2-1 and a movable bridging contact 215. The clips 33 21 are firmly mount.- ed on and insulated l'rom a supporting ba screwed onto the body of the laucet adjacent to the valve spindle and handle. The bridging contact 26 is lrietionally held between two insulating pieces 27 and 28 fixed to the spindle 29 so that it i rec to rotate therewith when unobstructed. The clips 23 24 and cooperating ships 26 limit th movement ot the contact, 20. he switch is connected in circuit with any suitable source of supply and the resistance unit if) by the leads 3t) ill 32 as clearly illustrated in l.

in the operation of the device, when the laucet is opened or closed the switch contact 28 moves with the spindle to cl "pen the circuit through the heater and a result of the frictional engagement between the blade 26 and the insulating blocks 27 and 28 when the spindle is rotated far enough to operate the switch its r0- tation in the direction may be continued to furrespectively.

tlierincreasethesupplyoi lluid when turningthe fauc t on or to further cut oil the supply when turning the faucet ol'l.

in the heater illustrated in Figs. 3 and'4 the central tube 10 of the [list form is replaced by a plurality of small tubes 10 located in close proximity to the interior of the heating unit 15. These tubes pass through and are fitted in heads ii and 33. The upper head ii is provided with cap 12" and the construction is such as to furnish a communicating passage between th e central tubes 1 and the outer return tube 20. The lower head {i3 is provided with an annular flange 34 which is firmly secured to the upper end of an exteriorly threaded tube Alter the heating unit has been slipped into position between the interior tubes l0 and the exterior tube 20, a ring 36, forced upward by a flanged coupling nut 17, holds it in position. This nut bears against the under side of the ring 36 and is screwed on to the exterior of the tubular member 35', it also draws the supply pipe 13 up against the lower end of the tube 35, and by this means and the interposed gasket 38 a fluid-tight connection is provided.

As in the heater shown in Fig. l, the course of the fluid in passing from the supply pipe '13" to the outlet 21 is up through the tubular member 35 and. the central pipes 10:, thence through the passage at the upper end of th'e heater and finally down through the exterior pipe 20 to the outlet 21. With this construction the fluid is brought nearer to the heat unit in its passage upwards through the heater than in the preceding form and the fluid is more rapidly heated with the same expenditure of energy.

In the form of the invention illustrated in Figs. 5 to 8 inclusive, central tubes 10 similar to the tubes 10* are employed and as in the preceding case are located in close proximity to the heating unit, but the exterior coiled tube 20 of the preceding form is replaced by a plurality of straight tubes 20'. in this form of the invention the course of the fluid is much longer than in the preceding forms, and the fluid is thereby retained in convective relation to the heating unit a considerably longertime than in the preceding forms. Thi increased length of flow is accomplished by the pipe end connections through the channeled caps '12' and 35" located at the upper and lower ends oi t he tubes The upper ends of the tubes are passed through and firmly secured to a llat head or plate ll" as in the preceding case; while the lower ends of the tubes are similarly pass d through and secured to flat concentric rings 32'," and Til space between the rings 33* and 33 is provided for the passage of the heat unit 15 in the assembling of the parts. \Yhcn this unit has been positioned, the caps 12" and 35" are set in place and drawn together against the llt'z'iil ii" and rings 33" and 33 by a bolt iii) which passes through the cap 12" and head ii and is screwed at its lower end into a suitable interiorly threaded boss onlhe upper side of the lower cap 33. These caps, as previously indicated, are provided with channels which consti tute communicating passages between th various tubes of the heater and a water-tight joint is insured 'e n the ("1 is and h llt"l(l ll in iie ca e, and the I L a plurality of ilnnl ('(Jllilliflllllg pipes located in heat con rings 33 and in the other, by suitable gaskets 4t) in lliCCtLPB so as to provide an unobstru ted pass-agibetween the tubes and the channels in the caps. The underside of the lower cap 35 is provided with an exteriorlythreaded boss against the lower end of which the supply pipe 13" is held by a. clamping nut 37". This boss is provided with a central opening 42.

From the inspection of Fig. 8 it will be seen that there are fifteen central or interior tubes and twenty exterior tubes. These are arrange; in concentric circles and for the purpose of tracing the How of the fluid through the heater may be considered as divided into ten groups. Of these there are five interior groups of three tubes each: and five exterior groups of four tubes each. As the fluid passes from one end of the heater to the other it passes through all tlie tubes of any one group in parallel. This will. be best understood by tracing thecourse of the fluid through the heater. This course is as follows: supply pipe 13 passages 42 43 to lower channel 44, up through the groups of tubescominunicating therewith to upper channel 45, down through the remaining group of tubes communicating with the channel 45130 the lower channel 46, thence up through the remaining group connecting therewith to upper channel 47, thence down to lower chann 4S and up to upper channel 49, thenceirom the inner set of tubes to the outer set by the channel 50 to the channel 51, thence down through the tubes communicating therewith to channel 52, thence up to upper channel 53, down to lower channel 54, up to upper channel 55, down to lower channel 56, and thence to the outlet pipe 57. From this course of the fluid it will be seen that it iscarried throughout the length of the heating unit five times by the tubes located interiorly of the unit, and five times by those located exteriorly. By

this arrangement a large heating surface is provided which may be utilized to give a wide temperature variation with a relatively small flow of fluid or a smaller temperature variation with a greater flow.

From the above description of these different forms of my invention it will be seen that by using a heating unit having acentral open space and utilizing both the interior and exterior surfaces of it a very compact and eliicient heater is obtained.

any alterations and modifications may be made in the onstructions illustrated and described herein without departing from thespirit and scope of my iiivention. For example, I may employ heating units of other crosssections than the circular cross-sections llll lfitlztlif l, and certain portions of the wall or walls may also be omitted altogether and many other changes in the form and shape of the heat unit may be made. I therefore do not wish to be limited, to the specific forms orlo the specific matter illustrated but wish to cover by the terms of the appended claims all legitimate alter-at ions and modifications.

What. i claim new and desire to secure by Letters Patent oi the United States, is:

i. In a fluid heater, the combination of a resistance unit having a central opening, ilnid conducting tubes extending lengthwise of said unit through said opening and over the outer walls of the unit, and suitable inlet and outlet openings and end onnections.

2. A lllilll heater comprising an electric resistance unit,

due-tin:- relation ther to, and means for rcmovably clamp- 4lprov1dedwith openings to register with the chann ls in: said unit in said heat conductiv relation.

26. A iluid heater comprising a helical resistance conductor, a plurality of fluid conducting pipes located in heat condnctive'relation thereto, and means for removably clamping said conductorin place.

4. A fluid heater comprising a heating unit consisting of a helical edgewise wound resistance ribbon conductor having its adjacent turns insulated from each other, a plurality of fluid conducting pipes located in heat conductive relation thereto, and clamping means engaging the opposite ends otsaid helix to hold the same in place.

5. A fluid heater comprising a central fluid conducting pipe, a laterally projecting head at one end thereof, an electric resistance unit associated with said pipe and bearing against said head, and means operatively connected to the other end of said pipe for pressing said unit against said head and holding it in place.

6. A fluid heater comprising one-or more fluid conducting pipes, heads located at the opposite ends thereof, an electric resistance unit associated with said pipes and engaging one of said heads, and means comprising a threaded connection with the other head for pressing said unit against said head and holding it in place.

"(i A fluid heater comprising one or more fluid conducting pipes, members located at opposite ends thereof, an electric resistance unit associated with said pipes in good heat conductive relation thereto, and means for clamping said unit between said members.

8, A fluid heater comprising one or more fluid conduct ing pipes, end members providing communication pas sages between said pipes, an eiectricreslstance unit associated with said pipes in good heat conductive relation thereto, and a bolt.for drawing said heads into firm engagement with said unit.

9. A fluid heater comprising an electric resistance unit having a central opening, fluid conducting tubes extending lengthwise of said unit through said opening and over the outer walls of the unit, suitable inlet and outlet openings therefor, and end members providing connecting passages between said tubes so arranged that the llaid as it passes through the heater passes throughout the length of the unit a plurality of times both intcrioriy and exieriorly thereof.

in witness whereof I have hereunto set my hand this 21st day of May, 1904.

GEORGE E. STEVENS.

Witnesses 1 Duoiuin McK. BICKILLOP: Jon) .1 WALKl-Jn. 

